theophylline potassium salt;K-theophylline;potassium salt of theophylline;Theophyllin-Kaliumsalz;3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione, potassium salt;potassium theophyllinate;potassium theophylline;theophylline-potassium;Potassium;1,3-dimethylpurin-9-ide-2,6-dione;potassium;1,3-dimethylpurin-9-ide-2,6-dione
New Antihistaminic Theophylline or Theobromine Derivatives
摘要:
A series of 3,4-dihydro-1,3-dimethyl-7-[3-(4-substituted-piperazin-1-yl)- substituted-alkyl]-1H-purine-2,6-diones and 3,7-dihydro-3,7-dimethyl-1-[3-(4-substituted-piperazin-1-yl)- substituted-alkyl]-1H-purine-2,6-diones was synthesized and evaluated for antihistaminic activity. Some of them displayed good inhibition of both histamine-induced bronchospasm in the anesthetized guinea pig at 10 micrograms/kg by the intravenous route and of passive cutaneous anaphylaxis in the rat at 10 mg/kg by the oral route. Comparison of the two most active compounds revealed a higher antihistaminic activity with the compounds containing a (phenylthio)propyl group (1 and 2) as compared with that containing a phenoxy group. Compound 2 [RS-49014, 3,4-dihydro-1,3-dimethyl-7-[3-[4-[3-(phenylthio)propyl]piperazin-1 -yl]- 2-hydroxypropyl]-1H-purine-2,6-dione] was selected for clinical trials on the basis of a comparative pharmacological study with chlorpheniramine, ketotifen, promethazine, and theophylline.